Substantial work disability and earnings losses in individuals less than age 65 with osteoarthritis: comparisons with rheumatoid arthritis.

Substantial earnings losses and work disability were seen in individuals less than age 65 with asymmetric oligoarthritis, a surrogate for osteoarthritis, almost as great as those seen with symmetric polyarthritis, a surrogate for rheumatoid arthritis. The proportions of individuals who were working was 66.7% for men and 35.5% for women with asymmetric oligoarthritis, compared to 56.1% and 31.0% of those with symmetric polyarthritis, and 89.4 and 61.6% of those with no arthritis. Rates of work disability in individuals with asymmetric oligoarthritis involving one knee or one hip were in the same range as those in individuals with symmetric polyarthritis involving two knees or two hips. The earnings of women and men with asymmetric oligoarthritis were only 30 and 63% respectively of the earnings of persons with no arthritis. However, less than one-third of these earnings losses were explained by the presence of arthritis, with further explanation from higher age, lower formal education levels, and comorbidity in individuals with asymmetric oligoarthritis. These results suggest that greater attention to demographic and comorbidity variables may be indicated in efforts to control economic losses associated with arthritis.